Radio communication devices are known to operate with antennae for transmitting or receiving radio frequency (RF) signals within a communication environment. Typically, these antennae are designed to transmit or receive the signals found within desired bandwidths of RF frequencies. As a result, signals not found within the desired bandwidths are not transmitted or received as efficiently.
As is known in the art of antenna design, impedance mismatch between an antenna and circuitry of a radio communication device causes a loss in the power of a signal being transmitted or received. For a transmitted signal, reflection of such a signal back to the circuitry typically accounts for some of the loss. Generally, reflected power of a transmitted signal does not cause any problems when its magnitude is small relative to the magnitude of what is transmitted. However, when the impendance mismatch exceeds a tolerable limit, the reflected power may damage sensitive components of the circuitry.
For radio communication devices with detachable antennae, mismatch conditions due to improper antenna connection or absence of a required antenna can also cause problems of reflected power. Typically, the absence of an antenna results in an open circuit mismatch condition where a transmitted signal is totally reflected. Consequently, this open circuit mismatch condition can seriously damage sensitive components. In the absence of feedback to users, these mismatch conditions may cause the user to perceive incorrectly that a radio communication device is faulty.